If you watched CBS 11 News at 6pm you saw me hold up hail stones from the big hail storms on Wednesday, June 13th. I also showed this graphic of how hail forms.

In a thunderstorm there is air moving upward into the sky. This air moving upward is what creates the thunderstorm.

Rain droplets form as the air cools as it rises. In the cloud temperature drop below freezing and above that is where hail forms. The hail stones grow larger as they move up and down in the thunderstorm updraft. Eventually either the hailstones get too large and fall to the ground or get blown out of the updraft.

In order to get baseball size hail you need that updraft in the thunderstorm to be moving more than 100 mph!